I ran the commands to change the serial number and system ID as the very first step before ever letting the SIM boot all the way up. I used the following specifically.
setenv bootarg.nvram.sysid 1111111111
When I ran the printenv command on both it shows they are both changed.
I then booted up the SIM and it failed to boot because no disks were found. I booted into maintenance mode and no disks were assigned. When I ran the disk assign all command I noticed the system ID was not changed. I ran sysconfig -v and saw the serial number had been changed but not the system ID.
I've read many posts on this and to be clear I am using the setenv command (not set) and I did run the printenv command to verify it changed. Even on the next boot I went back to the > prompt and it still showed both were set.
Is there a problem with the latest SIM not letting you set the system ID?
To be clear I did set both variables. In my case I found the value I set the sysid to in the SIM is not what actually got set. However, running the variable command did in fact give the SIM a different unique system ID.